Writing tablet



L. PONNOCK Jan. 16, 1945.

WRITING TABLET Filed Feb. 8, 1944 IN1/ENTOR- [emommc/ BY @ZUM fw ATTORNEYS.4

Patented Jan. 16, '1945 UNITED STATES PATENT OFFICE 2,367,608 WRITING TABLET Leon Ponnock, Philadelphia, Pa. Application February 8, 1944, Serial No. 521,502

5 Claims.

This invention relates to writing tablets. More specifically it has reference to a writing tablet f a kind wherein markings made by a stylus upon a transparent sheet are rendered visible through adherence of an associated semi-transparent backing sheet of light color along the lines of the markings, with the dark tacky surface of an underlying pad, and wherein the inscriptions disappear upon lifting of the impression and backing sheets from pressure contact withthe pad.

My invention has for its chief aims to enable production of writing tablets of the species referred to in quantity more expeditiously and economically than possible heretofore, and to render their impression and backing sheets more resistive to easy tearing and/or distortion incident to repeated usage of the tablets.

Other objects and attendant advantages will appear from the following detailed description of the attached drawing, wherein Fig. 1 is a perspective view of a writing tablet conveniently embodying my invention.

Figs. 2, 3, 4 and 5 are detail sectional views taken as indicated respectively by the angled arrows II--II, IIL-III, IV--IV and V-V in Fig. l.

With more detailed reference to the drawing, the numeral I0 designates the foundation member of the tablet which may be of relatively thick stiff cardboard and whereon is mounted a pad II of smaller area having a top surface coating I2 of dark tacky material. Overlying the pad II is a transparent impression sheet I3 of thin Celluloid or the like; and interposed between the pad and said sheet is a'semi-transparent sheet I4 of thin paper of light color, the two sheets beingv in this instance of the same size and area as said pad.

In accordance with my invention, the coinciding upper and lower edges of the impression and intermediate sheets I3 and I4 are bound by enveloping strips I5 and I6 of tape which may be of tough paper, and united preferably by stitching at I'I and I8.

For the purpose of securing the component parts of the tablet together, I employ staples such as indicated at I9 and 20. From Figs. 2 and 4 it will be noted that the staples I9 are passed through the sewed binding strip I5 which unites the upper edges of the sheets I3 and I4, through the pad II adjacent the upper edge of the latter, and finally through the foundation board I0, the ends of said staples being knocked over or clinched at the back of said board as shown in Fig. 4. The staples 20 are, however, utilized only to secure the pad II along its lower edge to the foundation board I0 as shown in Figs. 3 and5, the united lower edges of the sheets I3 and I4 being left free. As a consequence said sheets may be lifted out of adhering contact with the tacky surface of the pad II for cancelation of any markings 'previously made with the stylus upon the impression sheet.

From the foregoing it will be apparent that I have provided a Writing tablet with component parts prepared from inexpensive materials and secured together in a way which favors very'economic production on a large scale. In this connection it is pointed out that the binding strips v I5 and I6, inaddition to serving as a means for uniting the upper and lower edges of the sheets I3 and I4, effectively reinforce said edges against the possibility of easy tearing. Having thus described my invention, I claim:

1. In a writing tablet of the character described, a foundation board; a superposed pad having a tacky surface of dark color; a transparent impression sheet and an interposed semitranspaent backing sheet overlying the pad; fastening means by which the pad, the impression sheet and the backing sheet are secured adjacent their top edges to the foundation board; and separate fastening means whereby the pad only is secured adjacent its lower edge to the foundation board so that the lower edges of the impression and backing sheets are left free to be lifted for cancelation of markings previously made upon said impression sheet.

2. A writing tablet according to claim 1, wherein the securing means comprises a plurality of clinch staples.

3. A writing tablet according to claim 1, wherein the top and the bottom edges of the impression and backing sheets are secured together by and reinforced with enveloping binding strips.

4. A writing tablet according to claim 1, wherein reinforcing binding strips envelop the top and bottom edges of the impression and backing sheets and are secured by sewing.

5. A writing tablet according to claim 1, wherein the semi-transparent backing sheet is attached along its upper and lower edges to the correspending edges of the impression sheet by enveloping binding strips; and wherein the securing means for the upper edges of the pad and impression sheet also serves to secure the upper one of the two binding strips.

LEON PONNOCK. 

